Page:Popular Science Monthly Volume 14.djvu/738

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THE POPULAR SCIENCE MONTHLY.

Mr. Watson did not announce his observation of the second star till three weeks after the eclipse, and after he had revised in detail the conditions of his observation. Here is proof that this star had made a less impression on him than the first. But now the first is between the fourth and fifth magnitudes, and the second only between the fifth and the sixth.

In any case, we can not but hold that the positions given are highly doubtful and can not be seriously assumed as a basis for calculating orbits, as has been done at the observatory.

Mr. Swift writes, "I have no doubt that one of the two stars was Theta Caneri, and the other the intra-Mercurial planet."

But if one of the two stars seen by Professor Watson is Theta Caneri, the other, whose difference from the former is, according to him, 18m 57s more to the west, and 13' more to the south, comes exceedingly near to Zeta Caneri, whose difference from Theta is 19m 25s also to the west, and 30' also to the south. If this star were a planet it would not have been possible to see it without at the same time seeing Zeta, which would have been quite near; but of Zeta our American astronomers do not speak.

Mr. Swift, however, answers this objection by saying that he saw simultaneously Theta and the planet, and states the difference between them as follows:

Right ascension. Declination.
Star Theta, 8h 24m 40s 18° 30' 20"
Planet, 8h 26m 40s 18° 30' 25"